Microsoft announced a new, simplified scheme for determining how long it will support its products. Most small businesses and home users upgrade often enough that the details don’t matter – the products are supported for a good long time. The announcement mostly gives big companies predictable timetables on which to base their licensing and upgrade plans. (Here’s an article about the details, if you’re curious.)
There is an interesting inference to be drawn, though. Microsoft had claimed there would not be another major Windows release until a radically new version is ready – code-named “Longhorn” and not expected for several years. A lot of people were skeptical, thinking that Microsoft would surely create some interim release – the way Windows ME padded the release schedule until Windows XP was ready. But the new support timelines lend credence to the claim that there won’t be a new Windows version until Longhorn. It could be that Microsoft’s Trustworthy Computing initiative will cause the company to spend the next few years improving the security of Windows XP before it introduces any exciting new functionality.